It is highly likely that these defects were the major cause of neonatal lethality in knockout mice models, thus indicating that the loss of RTL1 is a major cause of muscular hypotonia and feeding difficulty/poor sucking function seen in Temple syndrome, and that the overproduction of RTL1 induced by loss of RTL1as is a major cause of the respiratory problems and diastasis recti damage in Kagami-Ogata syndrome. This evidence concerns the gene RTL1 and motor developmental delay due to 14q32.2 paternally expressed gene defect.